 /*******************************************************************************
  * Copyright (c) 2000, 2006 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  * IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.ui.internal.ide.registry;

 /**
  * Instances of this class represent the result of a specific marker
  * query. Specifically they contain an ordered collection of marker
  * attribute values.
  */

 public class MarkerQueryResult {
     /**
      * An ordered collection of marker attribute values.
      */
     private String [] values;

     /**
      * Cached hash code value
      */
     private int hashCode;

     /**
      * Creates a new marker query result with the given values.
      * <p>
      * The values may not be empty.
      * </p>
      *
      * @param markerAttributeValues the target marker's attribute values
      */
     public MarkerQueryResult(String [] markerAttributeValues) {
         if (markerAttributeValues == null) {
             throw new IllegalArgumentException ();
         }
         values = markerAttributeValues;
         computeHashCode();
     }

     /* (non-Javadoc)
      * Method declared on Object.
      */
     public boolean equals(Object o) {
         if (!(o instanceof MarkerQueryResult)) {
             return false;
         }

         if (o == this) {
             return true;
         }

         MarkerQueryResult mqr = (MarkerQueryResult) o;
         if (values.length != mqr.values.length) {
             return false;
         }

         for (int i = 0; i < values.length; i++) {
             if (!(values[i].equals(mqr.values[i]))) {
                 return false;
             }
         }

         return true;
     }

     /* (non-Javadoc)
      * Method declared on Object.
      */
     public int hashCode() {
         return hashCode;
     }

     /**
      * Computes the hash code for this instance.
      */
     public void computeHashCode() {
         hashCode = 19;

         for (int i = 0; i < values.length; i++) {
             hashCode = hashCode * 37 + values[i].hashCode();
         }
     }
 }

